<div class="collection-item clearfix">
    <div class="course-item" 
        style="background: url(<%= IMG_BASE_URL+item.posterUrl%>) no-repeat; background-size:100% 100%;"
    >
    <h1 class="collection-tt"><%= item.title %> </h1>
    <a href="<%= item.qqQunLink %> " class="btn"></a>
    </div>
</div>